Correct Answer: D

Rationale: Increased urine output is often the first sign that acute glomerulonephritis is improving, as it indicates a reduction in fluid retention and better kidney function. Stabilization of blood pressure and other symptoms typically follow.

Correct Answer: B

Rationale: The peak age for the onset of acute poststreptococcal glomerulonephritis is typically between 5 and 7 years old. This age group is most affected due to the higher incidence of streptococcal infections in school-aged children, which can lead to this renal complication.

Correct Answer: C

Rationale: Vegetables, particularly pureed ones, are often recommended as a first solid food for infants because they are easy to digest and less likely to cause allergies. Fruits can be introduced later due to their natural sweetness, while eggs and meat are typically introduced after fruits and vegetables as they may pose a higher risk of allergies.

Correct Answer: C

Rationale: Water and sodium retention is a major complication in chronic renal failure, leading to hypertension and edema. Hypokalemia and metabolic alkalosis are less common, and while BUN levels rise, retention rather than excretion is problematic in chronic renal failure.

Correct Answer: B

Rationale: Hematuria (blood in the urine) and proteinuria (protein in the urine) are common findings in acute glomerulonephritis due to inflammation of the glomeruli. Bacteriuria and changes in specific gravity are not as directly associated with this condition.